Improved lifting-jack



UNITED STATES PATENT OFFICE. f

H. S. SHEPARDSON, OF SHELBURNE FALLS, MASSACHUSETTS,'ASSIGNOR TO H. S.SHEPARDSON 85 OO., OF SAME PLACE.

IMPROVED LlFTlNG-JACK.

Specication forming part of Letters Patent No. 50,306, dated October 3,1865.

To all whom it may concern.:

Be it known that I, H. S. SHEPARDsoN, ot' Shelburne Falls, in the'countyof Franklin and State of Massachusetts, have invented certain new anduseful Improvementsin Lifting- Jacks; and I do hereby declare thefollowing to be a full, clear, and exact description ofthe constructionand operation thereof, reference being had to the laccompanyingdrawings, making a part ot' this specification, in which- Figure lrepresents a side view ot the jack run down to its lowest position. Fig.2 represents an edge view thereof; and Fig. 3 represents the jack as runup and locked bythe gear which moves it.

Similar letters ot' reference where they occur in the several n'guresdenot-e like parts of thejack in all the drawings.

My invention consists in certain mechanism for running up thejack andforlocking it and its load when up by the same mechanism.

To enable others skilled in the art to make and use my invention, l willproceed to describe the same with reference to the drawings.

A represents the base ot' the jack, and B a permanent upright securedthereto.

O is the movable portion of the jack, and united to the stationary orimmovable portion B by set-screws a passing through slots bin the part Oand into the partB, so that the part O may move up and down on the partB. On the part B there is pivoted a toothed arc, D, to which a handle orlever, E, is attached, so that said arc may be readily turned by it; andupon the part Gis pivoted, as at c, an arm, F, that has a concave rack,d, upon it that can be thrown in and out of gear with the circular arcD, as may be required. When the jack is run down, as in Fig. l, the armF swings back until it comes against the stud e, where it stops, and isheld with its rack d in gear with the arc D. When the part O is run upwith its load, as seen in Fig. 3, the arc D comes -against a stud orstop,j`, and in `that position,

the last tooth of the rack being in gear with the last Atooth of theare, the hand may be removed from the lever, and the part O will remainlocked up until again let down by raising the lever E.

That thejack may be adapted to the raising of' carriages (to whichpurpose it. is most generally applied) and to the varying height ofaxles therein, the upper portion ot' the movable part O is stepped olf,as at g, and below these steps are a series ot' holes, h, into any oneof which a pin may be placed, so that under almost any cireumstancesasingle sweep ot' the lever E and its toothed arc D will raise the loadand lock it up, as above stated, for any practical purpose.

For raising very heavy bodies or weights the teeth ot the arc, insteadot' having a radial pitch, as is common in gear-wheels, may be inclinedmore in a line under the Weight that it sustains, and the teeth orcogs(l ofthe arm F should be correspondingly inclined, and thus thesuperincumbent weight or pressure, instead ot tending to throw the armont ot' gear with the arc, would tend t0 hold them together, or at leastrender them passive.

Having thus fully described the nature, object, and purpose ot' myinvention, whatIclaim therein as new, and desire to secure by LettersPatent, is-

In combination with the permanent portion B and the movable portion Got' the jack, the toothed arc D and swinging toothed arm F, operatingtogether for the purpose and in the manner substantially as hereindescribed and represented. I

H. S. SHEPARDSON.

Witnesses:

. ARTHUR MAXWELL,

J. H. WILDER.

